Covalent Organic Frameworks with Electron‐Rich and Electron‐Deficient Structures as Water Sensing Scaffolds

• Published in: Macromolecular rapid communications. Vol. 41; no. 24; pp. e2000003 - n/a
• Main Authors: Ma, Wenyue, Jiang, Shan, Zhang, Wei, Xu, Bin, Tian, Wenjing
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.12.2020
• Subjects: Catalysis; Control stability; Controllability; covalent organic frameworks (COFs); Crystal structure; Crystallinity; Electrons; electron‐rich and electron‐deficient structures; Fluorescence; Organic solvents; Porosity; Proton conduction; Scaffolds; Structure-function relationships; Thermal stability; Triazine; water detection; electron-rich and electron-deficient structures; water detection; covalent organic frameworks (COFs)
• ISSN: 1022-1336; 1521-3927; 1521-3927
• DOI: 10.1002/marc.202000003

Covalent organic frameworks (COFs) have potential applications in gas storage, catalysis, proton conduction, sensing, and chemical removal etc., due to their highly crystalline structure, good stability, porosity, as well as structural and functional controllability. Herein, by using electron‐rich group, 2,5‐bis(methylthio)terephthalaldehyde (BMTA), and electron–deficient group, 1,3,5‐tris‐(4‐aminophenyl)triazine (TAPT) as building blocks, TAPT‐BMTA‐COF is constructed through Schiff‐base reaction. TAPT‐BMTA‐COF has high crystallinity, porosity, big Brunauer−Emmett−Teller surface area (BET), good chemical and thermal stability, and commendable solvatochromic properties. It can be used as the water sensing scaffold to detect the trace water in organic solvents due to the fluorescence quenching of the COF caused by the interaction between water and TAPT‐BMTA‐COF. Luminescent TAPT‐BMTA‐covalent organic frameworks (COF) with an electron‐rich group and an electron‐deficient group have a special response to water. The fluorescence of the COF can be quenched by increasing of water content in organic solvents due to the interaction between water molecules and TAPT‐BMTA‐COF. By using this property, trace amount of water in organic solvents can be detected according to fluorescent change of the COF.